This letter was written to the wife of Omosu in acknowledgment of offerings Nichiren Daishonin had received from her at the beginning of the year. The precise year of this letter, however, remains unclear.

Omosu derived his name from that of the area in which his estate waslocated, Omosu Village in Fuji District of Suruga Province. His full name was Ishikawa Shimbei Yoshisuke. His wife was the elder sister of Nanjō Tokimitsu.

In this letter, Nichiren Daishonin explains the operative principle of the Ten Worlds in a simple, poetic way, revealing that both Buddhahood and hellexist within the life of each individual. A person with a heart full of hatred experiences the world of hell; a person with faith in the Lotus Sutraexperiences the world of Buddhahood.

https://www.nichirenlibrary.org/en/wnd-1/Content/172